running "cargo doc" causes the compiler to panic

[nicklaswj]

When I run cargo doc in one of my crates (that I unfortunately can't show you) the compiler panics
at a seemingly random dependency, i.e. it changes from run to run.
I use rust stable:

rustc 1.30.0 (da5f414c2 2018-10-24)
binary: rustc
commit-hash: da5f414c2c0bfe5198934493f04c676e2b23ff2e
commit-date: 2018-10-24
host: x86_64-unknown-linux-gnu
release: 1.30.0
LLVM version: 8.0

This is the full output of "cargo doc":

$ RUST_BACKTRACE=1 cargo doc                                                                                                                                             101 ↵
 Documenting bytes v0.4.10                                                                                                                                                       
    Checking uuid v0.6.5                                                                                                                                                         
    Checking rand v0.3.22                                                                                                                                                        
 Documenting futures-cpupool v0.1.8                                                                                                                                              
 Documenting uuid v0.6.5                                                                                                                                                         
 Documenting rand v0.3.22                                                                                                                                                        
 Documenting resolv-conf v0.6.1                                                                                                                                                  
 Documenting msdos_time v0.1.6                                                                                                                                                   
 Documenting mio v0.6.15                                                                                                                                                         
 Documenting num-traits v0.2.6                                                                                                                                                   
 Documenting typenum v1.10.0                                                                                                                                                     
    Checking tokio-timer v0.2.6                                                                                                                                                  
    Checking tokio-current-thread v0.1.3                                                                                                                                         
error: internal compiler error: librustc/traits/structural_impls.rs:178: impossible case reached                                                                                 
                                                                                                                                                                                 
thread '<unnamed>' panicked at 'Box<Any>', librustc_errors/lib.rs:587:9                                                                                                          
 Documenting tokio-timer v0.2.6                                                                                                                                                  
stack backtrace:                                                                                                                                                                 
   0: std::sys::unix::backtrace::tracing::imp::unwind_backtrace                                                                                                                  
             at libstd/sys/unix/backtrace/tracing/gcc_s.rs:49                                                                                                                    
   1: std::sys_common::backtrace::print                                                                                                                                          
             at libstd/sys_common/backtrace.rs:71                                                                                                                                
             at libstd/sys_common/backtrace.rs:59                                                                                                                                
   2: std::panicking::default_hook::{{closure}}                                                                                                                                  
             at libstd/panicking.rs:211                                                                                                                                          
   3: std::panicking::default_hook                                                                                                                                               
             at libstd/panicking.rs:227                                                                                                                                          
   4: std::panicking::rust_panic_with_hook                                                                                                                                       
             at libstd/panicking.rs:477                                                                                                                                          
   5: std::panicking::begin_panic                                                                                                                                                
   6: rustc_errors::Handler::bug                                                                                                                                                 
   7: rustc::util::bug::opt_span_bug_fmt::{{closure}}                                                                                                                            
   8: rustc::ty::context::tls::with_opt::{{closure}}                                                                                                                             
   9: rustc::ty::context::tls::with_context_opt                                                                                                                                  
  10: rustc::ty::context::tls::with_opt                                                                                                                                          
  11: rustc::util::bug::opt_span_bug_fmt                                                                                                                                         
  12: rustc::util::bug::bug_fmt                                                                                                                                                  
  13: rustc::traits::structural_impls::<impl rustc::ty::context::Lift<'tcx> for rustc::traits::SelectionError<'a>>::lift_to_tcx                                                  
  14: rustc::ty::context::TyCtxt::lift_to_global                                                                                                                                 
  15: rustc::traits::select::SelectionContext::candidate_from_obligation                                                                                                         
  16: rustc::traits::select::SelectionContext::evaluate_stack                                                                                                                    
  17: rustc::dep_graph::graph::DepGraph::with_anon_task                                                                                                                          
  18: rustc::traits::select::SelectionContext::evaluate_predicate_recursively                                                                                                    
  19: rustc::infer::InferCtxt::probe                                                                                                                                             
  20: <&'a mut I as core::iter::iterator::Iterator>::next                                                                                                                        
  21: <alloc::vec::Vec<T> as alloc::vec::SpecExtend<T, I>>::from_iter                                                                                                            
  22: rustc::traits::select::SelectionContext::candidate_from_obligation_no_cache                                                                                                
  23: rustc::dep_graph::graph::DepGraph::with_anon_task                                                                                                                          
  24: rustc::traits::select::SelectionContext::candidate_from_obligation                                                                                                         
  25: rustc::traits::select::SelectionContext::evaluate_stack                                                                                                                    
  26: rustc::dep_graph::graph::DepGraph::with_anon_task                                                                                                                          
  27: rustc::traits::select::SelectionContext::evaluate_predicate_recursively                                                                                                    
  28: rustc::infer::InferCtxt::probe                                                                                                                                             
  29: <&'a mut I as core::iter::iterator::Iterator>::next                                                                                                                        
  30: <alloc::vec::Vec<T> as alloc::vec::SpecExtend<T, I>>::from_iter                                                                                                            
  31: rustc::traits::select::SelectionContext::candidate_from_obligation_no_cache                                                                                                
  32: rustc::dep_graph::graph::DepGraph::with_anon_task                                                                                                                          
  33: rustc::traits::select::SelectionContext::candidate_from_obligation                                                                                                         
  34: rustc::traits::select::SelectionContext::evaluate_stack                                                                                                                    
  35: rustc::dep_graph::graph::DepGraph::with_anon_task                                                                                                                          
  36: rustc::traits::select::SelectionContext::evaluate_predicate_recursively                                                                                                    
  37: rustc::infer::InferCtxt::probe                                                                                                                                             
  38: <&'a mut I as core::iter::iterator::Iterator>::next                                                                                                                        
  39: <alloc::vec::Vec<T> as alloc::vec::SpecExtend<T, I>>::from_iter                                                                                                            
  40: rustc::traits::select::SelectionContext::candidate_from_obligation_no_cache                                                                                                
  41: rustc::dep_graph::graph::DepGraph::with_anon_task                                                                                                                          
  42: rustc::traits::select::SelectionContext::candidate_from_obligation                                                                                                         
  43: rustc::traits::select::SelectionContext::evaluate_stack                                                                                                                    
  44: rustc::dep_graph::graph::DepGraph::with_anon_task                                                                                                                          
  45: rustc::traits::select::SelectionContext::evaluate_predicate_recursively                                                                                                    
  46: rustc::infer::InferCtxt::probe                                                                                                                                             
  47: <&'a mut I as core::iter::iterator::Iterator>::next                                                                                                                        
  48: <alloc::vec::Vec<T> as alloc::vec::SpecExtend<T, I>>::from_iter                                                                                                            
  49: rustc::traits::select::SelectionContext::candidate_from_obligation_no_cache                                                                                                
  50: rustc::dep_graph::graph::DepGraph::with_anon_task                                                                                                                          
  51: rustc::traits::select::SelectionContext::candidate_from_obligation                                                                                                         
  52: rustc::traits::select::SelectionContext::evaluate_stack                                                                                                                    
  53: rustc::dep_graph::graph::DepGraph::with_anon_task                                                                                                                          
  54: rustc::traits::select::SelectionContext::evaluate_predicate_recursively                                                                                                    
  55: rustc::infer::InferCtxt::probe                                                                                                                                             
  56: <&'a mut I as core::iter::iterator::Iterator>::next                                                                                                                        
  57: <alloc::vec::Vec<T> as alloc::vec::SpecExtend<T, I>>::from_iter                                                                                                            
  58: rustc::traits::select::SelectionContext::candidate_from_obligation_no_cache                                                                                                
  59: rustc::dep_graph::graph::DepGraph::with_anon_task                                                                                                                          
  60: rustc::traits::select::SelectionContext::candidate_from_obligation                                                                                                         
  61: rustc::traits::select::SelectionContext::evaluate_stack                                                                                                                    
  62: rustc::dep_graph::graph::DepGraph::with_anon_task                                                                                                                          
  63: rustc::traits::select::SelectionContext::evaluate_predicate_recursively                                                                                                    
  64: rustc::infer::InferCtxt::probe                                                                                                                                             
  65: <&'a mut I as core::iter::iterator::Iterator>::next                                                                                                                        
  66: <alloc::vec::Vec<T> as alloc::vec::SpecExtend<T, I>>::from_iter                                                                                                            
  67: rustc::traits::select::SelectionContext::candidate_from_obligation_no_cache                                                                                                
  68: rustc::dep_graph::graph::DepGraph::with_anon_task                                                                                                                          
  69: rustc::traits::select::SelectionContext::candidate_from_obligation                                                                                                         
  70: rustc::traits::select::SelectionContext::evaluate_stack                                                                                                                    
  71: rustc::dep_graph::graph::DepGraph::with_anon_task                                                                                                                          
  72: rustc::traits::select::SelectionContext::evaluate_predicate_recursively                                                                                                    
  73: rustc::infer::InferCtxt::probe                                                                                                                                             
  74: <&'a mut I as core::iter::iterator::Iterator>::next                                                                                                                        
  75: <alloc::vec::Vec<T> as alloc::vec::SpecExtend<T, I>>::from_iter                                                                                                            
  76: rustc::traits::select::SelectionContext::candidate_from_obligation_no_cache                                                                                                
  77: rustc::dep_graph::graph::DepGraph::with_anon_task                                                                                                                          
  78: rustc::traits::select::SelectionContext::candidate_from_obligation                                                                                                         
  79: rustc::traits::select::SelectionContext::evaluate_stack                                                                                                                    
  80: rustc::dep_graph::graph::DepGraph::with_anon_task                                                                                                                          
  81: rustc::traits::select::SelectionContext::evaluate_predicate_recursively                                                                                                    
  82: rustc::infer::InferCtxt::probe                                                                                                                                             
  83: <&'a mut I as core::iter::iterator::Iterator>::next                                                                                                                        
  84: <alloc::vec::Vec<T> as alloc::vec::SpecExtend<T, I>>::from_iter                                                                                                            
  85: rustc::traits::select::SelectionContext::candidate_from_obligation_no_cache                                                                                                
  86: rustc::dep_graph::graph::DepGraph::with_anon_task                                                                                                                          
  87: rustc::traits::select::SelectionContext::candidate_from_obligation                                                                                                         
  88: rustc::traits::select::SelectionContext::evaluate_stack                                                                                                                    
  89: rustc::dep_graph::graph::DepGraph::with_anon_task                                                                                                                          
  90: rustc::traits::select::SelectionContext::evaluate_predicate_recursively                                                                                                    
  91: rustc::infer::InferCtxt::probe                                                                                                                                             
  92: <&'a mut I as core::iter::iterator::Iterator>::next                                                                                                                        
  93: <alloc::vec::Vec<T> as alloc::vec::SpecExtend<T, I>>::from_iter                                                                                                            
  94: rustc::traits::select::SelectionContext::candidate_from_obligation_no_cache                                                                                                
  95: rustc::dep_graph::graph::DepGraph::with_anon_task                                                                                                                          
  96: rustc::traits::select::SelectionContext::candidate_from_obligation                                                                                                         
  97: rustc::traits::select::SelectionContext::evaluate_stack                                                                                                                    
  98: rustc::dep_graph::graph::DepGraph::with_anon_task                                                                                                                          
  99: rustc::traits::select::SelectionContext::evaluate_predicate_recursively                                                                                                    
 Documenting tokio-current-thread v0.1.3                                                                                                                                         
                                                                                                                                                                                 
note: the compiler unexpectedly panicked. this is a bug.                                                                                                                         
                                                                                                                                                                                 
note: we would appreciate a bug report: https://github.com/rust-lang/rust/blob/master/CONTRIBUTING.md#bug-reports                                                                
                                                                                                                                                                                 
note: rustc 1.30.0 (da5f414c2 2018-10-24) running on x86_64-unknown-linux-gnu                                                                                                    
                                                                                                                                                                                 
error: Could not document `typenum`.                                                                                                                                             

Caused by:
  process didn't exit successfully: `rustdoc --crate-name typenum /home/nicklas/.cargo/registry/src/github.1485827954.workers.dev-1ecc6299db9ec823/typenum-1.10.0/src/lib.rs --cap-lints allow --color always -o /home/nicklas/Documents/work/CMP/code/cmp_dem/target/doc -L dependency=/home/nicklas/Documents/work/CMP/code/cmp_dem/target/debug/deps` (exit code: 1)
warning: build failed, waiting for other jobs to finish...
error: build failed 

[steveklabnik]

Can you try on nightly? We recently fixed a rustdoc ICE, I wonder if it's similar.

[nicklaswj]

I've deleted my last two comments... I'm running nightly now, hang on ;)

[nicklaswj]

Nightly doesn't panic, however I'm hitting another error where the Diesel documentation won't compile.
I don't know if it's unrelated error but I'm attaching it here just in case.
error.txt

Edit: It looks like nightly works, and I'm hitting a bug in the diesel crate instead, right?

[Aaron1011]

The issue appears to be caused by Rustdoc not handling overflow during projections. I believe we need to extend #54199 to cover all cases of overflows during selection.

[pietroalbini]

Duplicate of #52873